In facilities such as data centers, efficient placement and operation of server computers is required. For example, as an information processing system, a rack server is configured by mounting a plurality of server computers and a power supply device on a rack, so that the integration density of the physical servers is increased.
In this case, the plurality of server computers share the power supply device, and they share it within an upper limit power value set on the power supply device in total. However, the servers may be brought into a high-load state during operation, and there is a fear that the total power exceeds the upper limit power value set on the power supply device. In order to respond to such a situation, in Patent Document 1, power control on each of the servers is executed so that the total power does not exceed the upper limit power value set on the power supply device.    Patent Document 1: Japanese Unexamined Patent Application Publication No. JP-A 2012-226496
However, in a case where power control on each of the server computers is executed in consideration of the upper limit power value of the whole system as described above, there is a fear that the arithmetic processing performance of the server computers considerably deteriorates. This is because the arithmetic processing performance of the server computers are not necessarily proportional to power consumption. Then, the abovementioned technique causes a problem that, though system down due to power excess of the whole system can be avoided, the arithmetic processing performance of some of the server computers deteriorates and performance of the whole system deteriorates.